How to solve a nonogram

This post shows step-by-step how to solve a nonogram puzzle with pictures and by video. Download the free puzzle so you can work through it with me. 🙂

At the bottom of the page you can also sign up to download a free nonogram puzzle book containing 25 puzzles for beginners.

But wait! Have you heard of nonograms?

They’re logic puzzles that you solve by coloring in squares in a grid according to the instructions. When you’ve finished, you end up with a picture.

If you’re just starting out with nonogram puzzles, you may be finding all those numbers a little bit daunting! On this page I will show you how to solve a nonogram puzzle.

You can either see a video (see the heading “Video showing solving a nonogram puzzle” near the bottom of the page) or see a walkthrough step by step of solving a simple puzzle just below.

Step by step instructions for how to solve a nonogram puzzle

If you’d like to solve along with me, you can click on the puzzle below then save and print it. Any guesses what it might be yet?

To begin with all cells are unknown. I will mark a known black cell with a black square (no surprises there!) and any known white cells with a dot.

Complete lines

1. First find any solid lines. The 0 means there are no black cells in that row, so we mark every cell in the row with a dot (they are known white cells).

2. The 5 means that every cell in the row is black, so we color them all in.

3. Next we can look for any lines that can only be filled one way (ie those with only one white cell between blocks). The 2 / 2 row will be a complete row. There is only one possible way of filling it in – a block of 2 black followed by one white and then another block of two black.

4. After completing this row we can see that the first column has completed its block of two black. That means every other cell in this column must be white. So we can fill in the remaining cells with a dot. It’s important to mark any known white cells as this helps as you continue the puzzle.

Overlaps

5. Now I will show you another very important tactic – overlaps. In the 3 / 2 / 2 column, I use temporary marks to show the uppermost this set of blocks could go.

Then I start from the bottom to see the bottom-most these blocks can go.

Where the same blocks overlap, we know that must be a black cell, so we color those overlaps black.

6. We can use the overlap tactic again on the next column:

7. In the next column, we can use the overlap method again but the block of 5 must include the two black cells already known.

Out of range

8. Now we’re going to check for cells that are out of range. I have numbered the column with the block of 5 so you can see the furthest that the 5-block will extend.

Any cells beyond that will be out of range of the 5-block. They must be white so we mark those cells with a dot.

Can you guess what the picture is yet?

9. Use the out of range tactic for the last column.

Repeat nonogram solving tactics

10. Use the overlap technique in the top row.

11. Use the out of range technique on the 2-block row a bit further down:

The picture is really beginning to take shape now!

12. On the next row down, you can see that the 2-block is complete, so all the rest of the cells in this row will be white – so we’ll put dots there.

13. And also the very next row has a complete block of 2, so fill in the rest of the row with dots:

14. As we keep going down, we can see there needs to be a block of 2 in the next row. There is only one place it can go:

Nearly there!

15. Look at the 2 / 3 / 2 column. The second block is a 3-block. So it is complete and there needs to be a space around it. So we should place a dot above that 3-block.

16. In the row where we just placed that dot, we can see that there is only one way to finish the block of 2.

17. Looking at the column where we just placed the dot, we can see that the 3-block is complete, so we can place a dot above it.

18. And finally we can make that last remaining cell black to satisfy the 3-block across and also the verticle 3-block.

Ta da!

Here it is sped up:

Printable version of these step-by-step instructions

Download a printable version of the nonogram step-by-step instructions.

Video showing solving a nonogram puzzle

If you’d prefer, here’s a video so you can see a puzzle being solved.

Free Nonogram Puzzle Book

If you’d like to try out some more of these puzzles on your own, here is a free nonogram puzzle book for you to download.

You can also get my booklet of 25 free nonogram puzzles for beginners if you are over 13 years of age by signing up for my nonogram puzzle newsletter. This book contains instructions, hints, and tips to help you to see how to solve nonogram puzzles.

Let me know if you have any questions 🙂